DE-A-197 28 775 describes an infusion bag with an injection part and a withdrawal part. The injection part is intended for delivery of a medicament by means of an injection syringe, whereas the withdrawal part is used for withdrawing the solution by means of a spike. The injection and withdrawal parts have a tubular connecting part that is sealed by a protective cap designed as a break-off part.
Tapered connections having a tapered stem and a tapered sleeve, the tapered surfaces of which are standardized, are known in medical technology for connecting medical implements. The tapered connections that are not lockable and have standardized tapered surfaces are referred to as Luer connectors and the lockable tapered connections are referred to as Luer lock connectors. The Luer connectors or Luer lock connectors with a tapered shaft are referred to as male connectors and connectors with a tapered sleeve are referred to as female connectors.
An infusion bag with connectors for delivering and withdrawing liquids is also known from DE-A-103 48 016. The connector for delivering a liquid permits connection of a conventional syringe to a tapered connection, in particular a Luer lock tapered connection, which does not have an injection needle. Since an injection needle having a small cross section is not required, relatively viscous active substances can also be injected rapidly. There is no risk of injury to the nursing staff. There is also no risk of the infusion bag being damaged. The possibility of screwing together the syringe and the connector ensures that the connection does not become detached. The connector has a self-sealing, slit membrane that is pierced by the tapered shaft of the syringe. After the tapered shaft is pulled out, the membrane closes again and therefore prevents the liquid from running out of the bag. The connector has proven successful in practice. However, a requirement for correct functioning of the known connector is that the membrane can open easily and reliably.
EP-A-0 681 493 describes a connector for connecting a syringe. However, the connector is based on a different functioning principle from the connector described above. The known connector has a hollow pin that is arranged within a stopper tightly sealing the connector. The pin has a plurality of lateral openings below its point. When the syringe is connected to the connector, the stopper surrounding the pin is displaced by the tapered shaft of the syringe such that the pin penetrates the tapered shaft. A liquid connection is therefore produced between the syringe and the connector via the lateral openings of the pin.
EP 0 309 771 A1 describes a device for injecting liquids into a channel of a cannula connecting piece. The device has a membrane that is pierced by a cannula upon connection of the cone of a syringe. In this case, the basic principle involves the tapered shaft of the syringe taking hold of a clamping sleeve that surrounds the membrane and is supported on a lower flange of the membrane. As a result, the membrane is pushed over the cannula. The production and assembly of the known device is relatively costly and complicated because of the additional clamping sleeve.
U.S. Pat. No. 7,396,051 B2 describes an arrangement of connectors, in which a membrane of one connector is penetrated by a hollow body, the hollow body advancing into a cylindrical body of the other connector. However, the cylindrical body is not the cone of a syringe.